Phylogenetic Analyses and Characterization of the VP7 Genes of Serotype G9 Rotaviruses Circulating in Nanjing (China), 2012-2013 / 病毒学报

Group-A rotaviruses are recognized as the most common cause of acute diarrhea. Phylogenetic analyses of the VP7 genes of rotaviruses circulating in Nanjing (China) could aid in the development of rotavirus vaccines. A total of 908 stool specimens were collected from patients suffering from acute diarrhea in Nanjing between October 2012 and December 2013, and were tested further for rotaviruses. Fifty rotavirus isolates selected randomly were typed by reverse transcription-polymerase chain reaction using serotype-specific primers for G genotyping. VP7 genes of 19 G9 strains were sequenced for further genetic characterization. Among the 908 stool specimens examined during the surveillance period, 103 (11.34%) were rotavirus-positive. G9 was the most predominant genotype (78.0%), followed by G2, G1 and G3. Sequence and phylogenetic analyses of the VP7 genes of serotype G9 rotaviruses revealed these strains to comprise two lineages (G9-VI, G9-III) and to be dominated by the G9-VI lineage (which belonged to a unique subcluster of Japanese and Chinese G9 strains). Amino-acid sequences of the four antigenic regions (A, B, C or F) were variant among a portion of strains, which may have contributed to the prevalence of G9 rotaviruses in this area.

Adjuvant effect of CTA1-DD/IgG on immune responses to mode antigen ovalbu-min / 中国免疫学杂志

Objective:To determine the immunological effects of a new type adjuvant CTA 1-DD/IgG.Methods:Intranasal im-munization of BALB/c mice with OVA in combination with adjuvant CTA 1-DD or CTA1-DD/IgG.Blood samples were subjected to OVA-specific IgG Abs detection and IgG subclass profiles assessment using ELISA.Splenic plasma cells secreting anti-OVA Abs were detected by ELISPOT.Results:CTA1-DD/IgG showed stronger activity in inducing OVA-specific IgG Abs and splenic Abs-secreting cells compared with CTA1-DD.The enhancement of IgG1,IgG2a and IgG2b Abs were observed,and the ratio IgG2a/IgG1 were >1 in both groups.Conclusion: CTA1-DD/IgG can exert enhanced adjuvant effects compared with CTA 1-DD.Mixed IgG subclasses are induced,indicating a more balanced Th1/Th2 response.